1. Field of the Invention
The present invention relates to a numerical controller for carrying out learning control for controlling machine tools and other equipment.
2. Description of the Related Art
Learning control for improving machining accuracy is adopted when repeatedly commanding the same command pattern and executing the same command pattern in predetermined cycles to perform machining action. In learning control in which the same pattern is repeated in predetermined cycles, the position deviation is sampled and the correction data for a single cycle is stored on the basis of the position deviation, and, of the correction data, the correction data during sampling corresponding to the same command pattern is added to the position deviation during the current sampling to perform correction, as exemplified in Japanese Patent Application Laid-open No. 6-309021. This learning control is repeatedly executed, the correction data is sequentially updated, and the position deviation is ultimately brought to a value that is approximately “0.” In this type of learning control, the position deviation is brought to a value that is approximately “0,” so high machining accuracy can be achieved.
As described above, learning control repeatedly executes machining such that the same operation pattern is generated by the same command pattern, so high precision machining can be carried out. Conventionally, however, this learning control is applied solely to binary operations in which the same operation pattern is generated, whereas in operation with an ordinary NC program (ISO/EIA format), the same operation pattern is not generated even when the same NC program is executed, so application is not made to NC programs.